Current Conditions

Arnold, Missouri

86°F30°C

Hot

Wind

S 8 mph13 km/h

Humidity

54%

Cloud Cover

As of Wednesday, September 2, 2026 at 9:45 PM CDT

Today's Outlook

Night

Mostly clear, with a low around 80°F26°C. Breezy from the S at 7 to 8 mph11 to 12 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Hot	High 101°F38°C	Low 77°F25°C	Precip 0 in0 mm—	Cloud 8%	Wind SSW 6 mph10 km/h	Thursday: Mostly clear and hot, with a high of 101°F38°C and morning low of 77°F25°C. Light wind from the SSW around 6 mph10 km/h. Heat risk in the afternoon. Thursday Night: Mostly clear, with a low around 80°F26°C. Breezy from the S at 7 to 8 mph11 to 12 km/h.
Hot	High 101°F38°C	Low 76°F25°C	Precip 0 in0.1 mm4%	Cloud 10%	Wind SSW 5 mph8 km/h	Friday: Mostly clear and hot, with a high of 101°F38°C and morning low of 76°F25°C. Light wind from the SW around 4 mph6 km/h. Heat risk in the afternoon. Friday Night: Mostly clear, with a low around 79°F26°C. Breezy from the SSW at 5 to 7 mph9 to 11 km/h.
Drizzle	High 100°F38°C	Low 78°F26°C	Precip 0.02 in0.5 mm29%	Cloud 28%	Wind WNW 4 mph7 km/h	Saturday: Partly cloudy and hot, with a high of 100°F38°C and morning low of 78°F26°C. Light wind from the NW around 3 mph5 km/h. 18% chance of drizzle in the afternoon. Heat risk in the afternoon. Saturday Night: Partly cloudy, with a low around 80°F27°C. Light wind from the SSE around 5 mph8 km/h. 29% chance of drizzle in the evening.
Drizzle	High 94°F35°CFeels 98°F37°C	Low 76°F24°C	Precip 0.02 in0.6 mm11%	Cloud 40%	Wind ENE 5 mph9 km/h	Sunday: Partly cloudy and hot, with a high of 94°F35°C and morning low of 76°F24°C. Light wind from the ENE around 5 mph9 km/h. 10% chance of drizzle in the morning. Heat risk in the afternoon. Sunday Night: Partly cloudy, with a low around 78°F26°C. Light wind from the ENE around 6 mph9 km/h. 11% chance of drizzle in the evening.
Clear	High 93°F34°C	Low 72°F22°C	Precip 0.02 in0.5 mm6%	Cloud 30%	Wind ESE 5 mph9 km/h	Monday: Partly cloudy and hot, with a high of 93°F34°C and morning low of 72°F22°C. Light wind from the ESE around 5 mph8 km/h. Monday Night: Partly cloudy, with a low around 75°F24°C. Light wind from the ESE around 6 mph9 km/h.
Hot	High 98°F37°C	Low 72°F22°C	Precip 0 in0.1 mm5%	Cloud 21%	Wind SSE 6 mph10 km/h	Tuesday: Mostly clear and hot, with a high of 98°F37°C and morning low of 72°F22°C. Breezy from the S at 6 to 7 mph9 to 11 km/h. Heat risk in the afternoon. Tuesday Night: Mostly clear, with a low around 74°F23°C. Breezy from the SSE at 7 to 9 mph11 to 14 km/h.
Hot	High 98°F37°C	Low 78°F25°C	Precip 0 in0.1 mm4%	Cloud 21%	Wind SSW 8 mph13 km/h	Wednesday: Mostly clear and hot, with a high of 98°F37°C and morning low of 78°F25°C. Breezy from the SSW at 8 mph13 km/h. Heat risk in the afternoon. Wednesday Night: Mostly clear, with a low around 79°F26°C. Breezy from the S at 8 to 9 mph13 to 15 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdaySep 3	101°F38°C	77°F25°C	0 in0 mm· —	8%	Hot	SSW 6 mph10 km/h
DayMostly clear and hot, with a high of 101°F38°C and morning low of 77°F25°C. Light wind from the SSW around 6 mph10 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 80°F26°C. Breezy from the S at 7 to 8 mph11 to 12 km/h.
	FridaySep 4	101°F38°C	76°F25°C	0 in0.1 mm· 4%	10%	Hot	SSW 5 mph8 km/h
DayMostly clear and hot, with a high of 101°F38°C and morning low of 76°F25°C. Light wind from the SW around 4 mph6 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 79°F26°C. Breezy from the SSW at 5 to 7 mph9 to 11 km/h.
	SaturdaySep 5	100°F38°C	78°F26°C	0.02 in0.5 mm· 29%	28%	Drizzle	WNW 4 mph7 km/h
DayPartly cloudy and hot, with a high of 100°F38°C and morning low of 78°F26°C. Light wind from the NW around 3 mph5 km/h. 18% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 80°F27°C. Light wind from the SSE around 5 mph8 km/h. 29% chance of drizzle in the evening.
	SundaySep 6	94°F35°C Feels 98°F37°C	76°F24°C	0.02 in0.6 mm· 11%	40%	Drizzle	ENE 5 mph9 km/h
DayPartly cloudy and hot, with a high of 94°F35°C and morning low of 76°F24°C. Light wind from the ENE around 5 mph9 km/h. 10% chance of drizzle in the morning. Heat risk in the afternoon. NightPartly cloudy, with a low around 78°F26°C. Light wind from the ENE around 6 mph9 km/h. 11% chance of drizzle in the evening.
	MondaySep 7	93°F34°C	72°F22°C	0.02 in0.5 mm· 6%	30%	Clear	ESE 5 mph9 km/h
DayPartly cloudy and hot, with a high of 93°F34°C and morning low of 72°F22°C. Light wind from the ESE around 5 mph8 km/h. NightPartly cloudy, with a low around 75°F24°C. Light wind from the ESE around 6 mph9 km/h.
	TuesdaySep 8	98°F37°C	72°F22°C	0 in0.1 mm· 5%	21%	Hot	SSE 6 mph10 km/h
DayMostly clear and hot, with a high of 98°F37°C and morning low of 72°F22°C. Breezy from the S at 6 to 7 mph9 to 11 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 74°F23°C. Breezy from the SSE at 7 to 9 mph11 to 14 km/h.
	WednesdaySep 9	98°F37°C	78°F25°C	0 in0.1 mm· 4%	21%	Hot	SSW 8 mph13 km/h
DayMostly clear and hot, with a high of 98°F37°C and morning low of 78°F25°C. Breezy from the SSW at 8 mph13 km/h. Heat risk in the afternoon. NightMostly clear, with a low around 79°F26°C. Breezy from the S at 8 to 9 mph13 to 15 km/h.
	ThursdaySep 10	94°F34°C Feels 97°F36°C	78°F26°C	0.06 in1.4 mm· 18%	38%	Drizzle	SSW 8 mph13 km/h
DayPartly cloudy and hot, with a high of 94°F34°C and morning low of 78°F26°C. Breezy from the SW at 8 mph13 km/h. 17% chance of drizzle throughout the day. Heat risk in the afternoon. NightPartly cloudy, with a low around 80°F27°C. Breezy from the SSW at 8 to 9 mph13 to 15 km/h. 18% chance of drizzle in the evening.
	FridaySep 11	90°F32°C	73°F23°C	0.09 in2.2 mm· 20%	46%	Drizzle	SSW 7 mph11 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the SW at 7 mph11 km/h. 15% chance of drizzle throughout the day. Humid. NightPartly cloudy, with a low around 76°F24°C. Breezy from the SSW at 7 mph11 km/h. 20% chance of drizzle throughout the night.
	SaturdaySep 12	90°F32°C	71°F22°C	0.08 in2 mm· 14%	44%	Drizzle	S 6 mph10 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 71°F22°C. Breezy from the SSW at 6 to 7 mph10 to 12 km/h. 14% chance of drizzle throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 6 to 7 mph10 to 11 km/h. 13% chance of drizzle throughout the night.
	SundaySep 13	89°F32°C	71°F22°C	0.12 in3 mm· 21%	48%	Showers	SSW 7 mph12 km/h
DayPartly cloudy and hot, with a high of 89°F32°C and morning low of 71°F22°C. Breezy from the SSW at 7 to 8 mph12 to 13 km/h. 21% chance of showers throughout the day. NightPartly cloudy, with a low around 73°F23°C. Breezy from the S at 7 mph11 km/h. 19% chance of drizzle throughout the night.
	MondaySep 14	87°F30°C	70°F21°C	0.13 in3.4 mm· 18%	48%	Showers	SSW 7 mph11 km/h
DayMostly cloudy and hot, with a high of 87°F30°C and morning low of 70°F21°C. Breezy from the SSW at 7 mph11 km/h. 18% chance of showers throughout the day. NightPartly cloudy, with a low around 72°F22°C. Breezy from the S at 6 to 7 mph10 to 12 km/h. 16% chance of showers throughout the night.
	TuesdaySep 15	86°F30°C	68°F20°C	0.11 in2.8 mm· 16%	47%	Drizzle	SE 6 mph10 km/h
DayPartly cloudy and hot, with a high of 86°F30°C and morning low of 68°F20°C. Breezy from the SE at 6 to 7 mph10 to 11 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 70°F21°C. Breezy from the SE at 6 to 7 mph10 to 11 km/h. 13% chance of drizzle throughout the night.
	WednesdaySep 16	85°F30°C	67°F19°C	0.09 in2.4 mm· 13%	42%	Drizzle	ESE 6 mph10 km/h
DayPartly cloudy and warm, with a high of 85°F30°C and morning low of 67°F19°C. Light wind from the SE around 6 mph10 km/h. 13% chance of drizzle throughout the day. NightPartly cloudy, with a low around 69°F21°C. Breezy from the ESE at 6 to 7 mph10 to 11 km/h. 12% chance of drizzle throughout the night.
	ThursdaySep 17	84°F29°C	65°F18°C	0.05 in1.3 mm· 13%	40%	Drizzle	E 6 mph10 km/h
DayPartly cloudy and warm, with a high of 84°F29°C and morning low of 65°F18°C. Light wind from the NNE around 6 mph10 km/h. 13% chance of drizzle throughout the day. NightPartly cloudy, with a low around 67°F20°C. Light wind from the ESE around 6 mph10 km/h. 13% chance of drizzle before dawn.

Nearby Cities

Oakville5 mi8 km Mehlville6 mi10 km Concord6 mi10 km Affton8 mi14 km Lemay9 mi14 km Kirkwood11 mi17 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 38.4328°N, 90.3776°W·Elevation: 184m·Timezone: America/Chicago·Population: 21,357